JP-A-08-295140 describes a hybrid vehicle having a differential gear unit including a first rotary element connected to an engine, a second rotary element connected to the first motor, and a third rotary element connected to driving wheels, and a second motor connected to the driving wheels. In the hybrid vehicle taught by JP-A-08-295140, a drive mode can be selected from an engine drive mode in which the vehicle is powered by the engine by controlling the first motor in a manner such that the second rotary element serves as a reaction element, and a motor drive mode in which the vehicle is powered by the second motor. According to the teachings of JP-A-08-295140, a one-way clutch and a control brake are disposed on an input shaft of the differential gear unit to propel the vehicle by the first and the second motors while stopping the engine even if a required drive torque is relatively large. In this case, specifically, the first rotary element serves as a reaction element, and the second rotary element serves as an input element. In addition, in order to power the vehicle by both motors without stopping the engine, a clutch is disposed between the input shaft of the differential gear unit and an output shaft of the engine so as to disconnect the engine from the differential gear unit.